Verifying Email Address Validity in PHP
Question:
While examining ways to assess email validity, I encountered websites claiming to achieve this task. However, is it feasible to check email validity solely using PHP?
Solution:
To ensure email validity, PHP provides dependable methods. Firstly, let's verify the domain's existence using the domain_exists function:
if(domain_exists($email)) { echo('This MX records exists; I will accept this email as valid.'); } else { echo('No MX record exists; Invalid email.'); }
Additionally, PHP's filter_var function checks if the email has a valid format:
if(filter_var($email, FILTER_VALIDATE_EMAIL)) { //Email is valid }
However, these methods don't guarantee the existence of the user's email on that domain. Here are some considerations to keep in mind:
- Connection Trick: Spammers use this technique to check emails, but some mail servers may prevent it, leading to false positives.
- IP Blacklisting: Verifying too many emails can lead to your server being blacklisted, blocking future email delivery.
- Forced Email Response: The most reliable method is to send an email with a verification link to the specified address. Users must click the link to confirm their email's existence.
The above is the detailed content of Can You Verify Email Address Validity Using Only PHP?. For more information, please follow other related articles on the PHP Chinese website!

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